Method of and means for drawing sheet-glass.



A. RASPILLAIRE.

METHOD OF AND MEANS FOR DRAWING SHEET GLASS. APPLICATION FILED AUG.7. 1914..

1,1 84,996. Patented May 30, 1916.

2 SHEETS-SHEET I.

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WWWMWMMMMMM/M/fl ATTORN EY Patented May 30, 1916.

2 SHEETSSHEET 2- A. RASPILLAIRE. METHOD OF AND MEANS FOR DRAWING SHEET GLASS.

I I a?) 'INVENTOR ATTORNEY WITNESSES a citizen of the United States, residing at Morgantown, in the county of Monongalia and State'of West Virginia, have invented a new and useful Method of and Means for v Drawing Sheet-Glass, of which the follows AUGUST RASPILLAIRE, or MORGANTOWN, wEs'r vrnemm.

METHOD or AND linens roanRAwmesnEEr-emss;

sa eof Letters wait! Patented May 30, 1916.

Application filed August 7, 1914. Serial No. 855,665.

To all 'uglwm it may concern:

Be it known that I, AUGUST RhsmLLAI E,

ing is a specification.

This inventlon has reference to drawing sheet glass, and its object is to make provision for the drawing of sheet glass whereby the drawn sheet will retain its full width without tendency to narrow during the drawing operation.

In drawing sheet glass it is customer to provide a piece of glass known as a ait which is dipped into a supplyofmolten glass, and this balt is slowly withdrawn from the molten glass carrying with it adherent glass in the form of a sheet which in thickness depends upon the degree of fluidity of the glass supply and the speed of movement 0 the bait away from the supply. 1

Heretofore difliculty has been encountered in the attempt to produceglass sheets by drawing, since as the bait recedes from the supply ofmolten glass there is a narrowing tendency ultimatel resulting in the cessation of the operatlon. By the present invention this narrowing tendency is overcome by the production of a-flow of the molten lass in. a direction awayfrom the side edges of the forming sheet, so that there is a constant tendency to widen the sheet, wherefore by a proper-balance of forces the sheet may be drawn to approximately even width throughout and as longlas may be practicable. This is brought about by producing anelongated supply of molten glass of'the desired consistency with the end portions of the supply flowing oppositely one from the other, and then as the glass sheet is formed,

the oppositely directed outflow of theglass at the end portions of the forming sheet maintains the width-of the sheet-and prevents any collapse of the side portions tending to narrow the sheet, the thickness of the sheet being maintained by a suitable regulation of the fluidity -of the' glass supply andthe speed of movement of the forming sheet away from.-the.sl'1pply.

The invention Wlll be best understood from aconsideration of the following. dc,

tailed description, taken in connection with "thefaccompa nying drawings forming part ::of thls speclfication, with the furtherunderstanding that while the drawings show a practical form of the invention, the latter' "is not confined to any strict conformity with the showing of thevdrawings, but, may be changed and modified so long as such changes and modlfications mark no material departure from the salient features of the invention. 1

In the drawings :Figure 1 is a section of an apparatus embodying the present invention, the section being taken on substantially the plane of the forming sheet of glass. Fig. 2 is a section on the line 2-2 of Fig. 1 witli'some parts shown in elevation.

. Fig." 3 is, asection on the line 33of' Fig. 2

but omitting any showing of'glass. Fig. 4 1s a section similar to that of Fig. 2 but showing a modification of the structure.

' Referring to the drawings there is shown a glass furnace 1 which may follow the usual lines of such a furnaceand hence no description of the furnace is needed, and the showing is more or less schematic.

' At one side of the furnace is a chamber 2 having a. front wall 3, side walls 4, and'a stepped cover 5 6, respectively. The chamber 2 is in communication with the interior of the furnace 1 by a passageway 7, so that the heat of the furnace is communicated to the chamber 2. The passageway 7 may be re- .stricted in area-as desired by a damper or door Smovablethrough the top 6 close to the opening 7 and entering the chamber 2 to any desired extent. Through the top 6 there is provided an opening 9 to which is fitted a plug '10 whereby the opening 9 may be closed or access to thechamber 2 may be had through this opening, as may be desired.

Withinthe chamber" 2 there is located a pot or glass receptacle 11 having a mouth portion 12 in underriding relation to the opening ,9, so that-whenever desired glass from the furnace 1' may be ladled into the pot or receptacle 11. 4

Between the covers 5 and 6 is an upright wall 13 which together with the cover member 6 and side members 14 inclose the main body of the pot or receptacle 11. From one side of the receptacle 11 there is an expanding portion 15 ending in an elongated the interior of the furnace 1.

trough 1,6 communicating with the expanding portion 15 by ports 17 near the ends of the trough 16, but it will be understood that while it. is preferred that the expanding duct 15 should communicate with the trough 16 by "the end ports 17, other ports may be.

provided, or the two ports 17 may be sufficiently elongated to coalesce into a single port, which may be nearly or' quite as extensive as the trough 16. At each end the trough. 16 has terminal prolongations or extensions 18. forming end walls for. the

trough, while these prolongations are eachprovided with a channel '19 slanting downwardly'from the corresponding end of the trough 16 toward the outer end of -the ex .tension 18. Underriding the outer end of each extension 18 is one end of 'a-trough 20, the other end of which is carried through the adjacent wall of the furnace 1 and discharges thereinto, the trough 20 slanting at,

a suitable angle to direct molten glass to The upright wall 13 extends below the top member 5 sufficiently to come into close relation to thetopportion of the expanding duct 15 and projecting inwardly from the wall 3 into close relation to the bottom of the 't-r0ugh16 -isaplate 21. The trough 16 with the downward projection of the wall 13 and the plate 21 define a chamber 22 in which the trough 16 is located, and wherein the trough is protected to a suflicient degree from the intensity of heat of the furnace.

The chamber 22 is entered by burners 23 .and other burners 24 are located'wherever expedient fora purpose which will present lifted asdesired.

lyappear.

- The top 5 immediately over the trough 16 is provided with an elongated opening 25 through which a glass sheet 26 is extracted a'sformed;

In order to start the glass sheet, there is provided a glass strip indicated at 27, and

which is knownas a bait. This bait is held by clamps28 supported by a hanger 29 suspended from acarrier 30 such as is used in glassworks for drawing glass, and which is assumedto be suspended by suitable devices whereby the; carrier- .may be lowered and In the drawings there is shown in the furthe the glass so 'la'dled is. indicated at 32. The

"pot 11 is maintained at such a heat that the glass will flow therefrom through the duct nace 1 a supply 31 of molten glass which is assumed to have the desired degree of fluidity. A portion of this glass is ladled into glass pot or receptacle 11, and in Fig. 2

15, and by way of the ports 17 into the trough" 161 and rising therein ultimately comesto the level of vthe channels 19 and I overflowing the upper ends of these channels gravitates along the declining or sloping surfaces of the channelsto finally fall into .erly heated for the the troughs 20 being conducted the latfluidity than elsewhere, so that it is more quickly chilled and solidified than would otherwise be the case, and the flow of glass through the} channels 19 is correspondingly sluggish. V

If, now, it be assumed that there is a supply ofmolten glass in the trough16 constantly fed by more fluid streams-entering the trough through the ports 17,there will be a constant outflow of molten glass from the ends of the trough 16 through the channels 19. The conditions are under these circu stances proper for the drawing of a glass pla e,' whereupon the bait 27 is lowered through the opening 25 until-engaging the surface ofthe glass within the trough, and this bait may be slightly longer than the the inner highends of. the channels 19, whereby the glass is outflowing from the trough. The molten glass adheres to the lower edgeof the bait which has been prop- V V purpose, and now the bait is lifted at a suitable speed drawing with it an amount of glass from the trough which quickly chills to a solid condition as it emerges from the chamber 22 'where the temperature may be relatively low, so that itihedmolten glass is relatively thick or semi- As the forming glass [plate is withdrawn from the trough 16 the supply is maintained by the higher level of molten glass within the receptacle 11, and by a proper regula tion of the heat the glass will flow from the receptacle 11 into the trough 16' at a proper; speed to maintain the level within the trough about constant, and also maintain the v at the ends of the trough through overflow the channels 19. The tendency of this overflow is to widen or spread out the glass sheet at such of the speed of withdrawal of the glass sheet and the temperature of 'themolten glass within the trough and at the overflow ends, the width of formity, whereby the tendency of the glass sheetto narrow is counteracted by the spreading of the glass sheet flow of molten glass at opposite ends of the feeding trough, the flow at one end being the forming glass sheet is maintained at a close approximation to uni-1 trough, so as to in a small measure overlap v point, but by a suitable regulation due to the 'outin a direction opposite to that at the other.

end. Since the thickness of the glass sheet is" dependent upon the speed of formation, a

pedient of adjustment of'speed'andtempen a'ture.

In Fig. 4 there is shown a chamber 2" in which is provided a sub-chamber 22 divided off from the chamber 2 by a plate 21 and a cover 5 provided with an opening 25 serves to close in the chamber 2 and the sub-chamber 22*. A pot or receptacle 11 is provided generally similar to the pot or receptacle 11, but in Fig. 4: the main part of the pot or receptacle 11 is lodged within the furnace 1 while a duct continuation 15 of the pot 11 is extended through the corresponding wall of the furnace 1 into the chamber 2 with a trough portion 16? lodged within the chamber section 22. Since the pot 11 is in part within the furnace 1 a support 33 is provided for upholding it. The structure of Fig. 4 is provided with return troughs 20 and burners 23, 24, as in the other form. Since the pot 11 is in part within the furnace 1 access to this pot for filling is had through an opening 34 in the corresponding wall of the furnace, this opening being, of course, closed when not in use. r

In Fig. 4 a supply of glass 31 is shown in the furnace 1 and the supply of glass 32 is shown in the pot 11 The operation of the invention as disclosed in Fig. 4 is the same as that shown in the other figures of the drawing.

It will be understood, of course, that wherever intense heat is to be withstoodrefractory material is used as is customary in the glass making industry. It is not uncommon to use rollers in the formation of sheet glass andtherefore it will be understood that rollers may be employed in conjunction with or independently of other means for raising the forming glass sheet. 1

What is claimed is I 1. The method of forming sheet glass, which consists in providing an elongated narrow bodyof molten glass with the end portions flowing downwardly away from the body of molten glass, and drawing the sheet from such elongated supply of molten glass with the side edges of the sheet being drawn directly from the down flowing end portions of the supply. 7

2. The method of forming sheet glass, which consists, in providing an elongated narrow body of molten glass with the end portions spontaneously flowing oppositely and downwardly away from the body of molten glass, the distance separating thfe opp ositely down-flowing end portions o body of glass being less than the width of the sheet to be drawn, anddrawing a glass sheet from such body of glass with the edge portions of the sheet encroaching on the down flowing end portions of said body of molten glass.

3. The method of drawing sheet glass,-

which consists in providing an elongated narrow body of molten glass with a constant'ly active replenishing supply therefor at a higher level, causing the end portionsvof the body of molten glass to gravitate in op-I posite directions away from the body of glass, and drawing a, sheet of glass from the body of molten glasswith the edge por tions of the sheet overlapping the downwardly flowing end portions of the body of glass. 4. which consists in withdrawing the glass in sheet-form from a supply of molten glass with those portions .of the supply from which the edges of the sheet. are directly drawn gravitating away from' the correaway from the corresponding portions of the body .of glass, and replenishing the body of glass from which the sheet is being drawn by directing additional supplies of molten glass to said body immediately adjacent to The method of drawing sheet glass,

the outflowing end portions of said body of glass.

6. A glass furnace having associated therewith-an elongated trough for containing molten glass and located at a higher level than the level of molten glass in'the furnace, said trough having overflow channels at opposite ends to produce a spontaneous flow of glass at said ends in opposite directions therefrom, and ducts for receiving the overflow and slanting toward and entera ing the furnace to direct the glass overflowing from the trough into said furnace, said trough being provided with a glass receptacle at a higher level than and discharging into the trough for receiving glass removed from the furnace to constitute a replenishing supply for the trough.

7. A glass furnace having associated therewith an elongated trough for contains ing molten glass and located at a higher level than the level of molten glass in the furnace, said trough having overflow channels at opposite ends to produce a spontaneous flow of glass at said ends in opposite directionstherefrom, and ducts for receiving the overflow and slanting toward and entering the furnace to direct the glass overflowing from the trough into said furnace, said trough being provided with a glass receptacle at a higher level than and discharging into the trough for receiving U glass removed from the furnace to consti as my own, I'have hereto afiixed my signatut argfplenishing iupply for the tirough, ture in the presence of two witnesses. an sai receptacle aving means 0 communieation with the trough entering the' AUGUST.RASPILLAIRE' 5 latter at the end portions of said trough ad. Witnesses: jacent to-the overflow channels. IDA BQSLEY,

In testimony that I claimthe foregoing ROBT. E. GUY. 

